Allen: 'High confidence' no more oil will flow into Gulf

BP announced a "significant milestone" Wednesday as it pumped mud into its blown-out well and a senior company official said the decision on how best to plug it with cement could be made later today.

"I think it went extremely well. We are very encouraged," BP senior vice president Kent Wells told reporters during an afternoon technical briefing. "We are looking at what would be the best way to do the cement. I think we are getting ourselves to a good place but we have not made a decision yet."

BP and government technicians may decide to plug the well with cement both from the top and the bottom.

"We're in a good place today, but we want to get it permanent over the near term, whether that's days or weeks," Wells said. When asked when he would be able to say the well is dead, he told reporters, "I'm looking forward to that day."

Retired Coast Guard Adm. Thad Allen said during a White House briefing that he has "high confidence" that no more oil will leak from BP's well.

The energy giant began the "static kill" procedure at 4 p.m. ET Tuesday, and workers stopped pumping mud in about eight hours after the effort achieved its "desired outcome."

BP is monitoring the well to ensure it remains static and Wells said it is unlikely more mud would be pumped down.

"The well pressure is now being controlled by the hydrostatic pressure of the drilling mud, the desired outcome of the static kill procedure," BP said in a statement.

In response to BP's progress, Obama said the long battle to stop the Gulf spill "is finally close to coming to an end" but cautioned that the cleanup is not over, the Oval reports.

Earlier, White House energy adviser Carol Browner said Wednesday during morning talk shows that a new assessment found 75% of the oil in the Gulf has been captured, burned off, evaporated or broken down. The estimates were provided by the National Oceanic and Atmospheric Administration and the Department of the Interior.

NOAA administrator Jane Lubchenco admitted in a statement that less oil on the surface does not mean there isn't oil still in the water column.

"Our scientists and external scientists believe that the vast majority of the oil has now been contained. ... And so, I think we're turning a corner here." Browner said in an interview with CNN's American Morning.

Browner called the static kill an "important step" but said the 'final kill-kill' will come from the two relief wells set to be completed in the next 10 to 14 days.

An 18,000-foot relief well BP has been drilling for the past three months will be used this month to execute a "bottom kill," in which mud and cement will be injected into the bedrock 2 1/2 miles below the seafloor to finish the job, Allen said.

"The ultimate -- the bottom kill, which will finally kill the well," Allen said, would come from a relief well 17,864 feet deep and nearly intersecting the bottom of the leaking well hole.

The relief well is about 4 feet, horizontally, from the leaking well, aimed nearly straight toward an intersection point about a hundred feet farther down. BP's engineers could begin magnetic steering tests needed to aim a relief well drill into the breached well by Thursday. If balmy weather continues in the Gulf, that intersection would take place within the next two weeks.

U.S. estimates released late Monday say the Gulf spill is the world's largest accidental release of oil ever into marine waters. Federal scientists announced that BP's well released 205.8 million gallons of oil into the Gulf of Mexico, which is far more than initial U.S. government or BP estimates.

These numbers far outstrip estimates for what has ranked as the world's largest unintentional spill -- Mexico's Ixtoc I, which gushed 138 million gallons into the Bay of Campeche in 1979. Larger amounts of oil were intentionally spilled in 1991 during the Persian Gulf War.

The Macondo well gushed 53,000 to 62,000 barrels a day from April 20 until it was capped July 15, according to scientists in the Flow Rate Technical Group, which is supervised by the U.S. Geological Survey and the U.S. Department of Energy. The scientists say their estimates are accurate to within 10%.

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